Support http/https URLs in uv python --python-downloads-json-url (#16542)

continuation PR based on #14687

---------

Co-authored-by: Geoffrey Thomas <geofft@ldpreload.com>
Co-authored-by: Aria Desires <aria.desires@gmail.com>

docs/reference/cli.md

@@ -3420,8 +3420,7 @@ uv python list [OPTIONS] [REQUEST]
 <p>Other command-line arguments (such as relative paths) will be resolved relative to the current working directory.</p>
 <p>See <code>--directory</code> to change the working directory entirely.</p>
 <p>This setting has no effect when used in the <code>uv pip</code> interface.</p>
-<p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-list--python-downloads-json-url"><a href="#uv-python-list--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations.</p>
-<p>Note that currently, only local paths are supported.</p>
+<p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-list--python-downloads-json-url"><a href="#uv-python-list--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations</p>
 </dd><dt id="uv-python-list--quiet"><a href="#uv-python-list--quiet"><code>--quiet</code></a>, <code>-q</code></dt><dd><p>Use quiet output.</p>
 <p>Repeating this option, e.g., <code>-qq</code>, will enable a silent mode in which uv will write no output to stdout.</p>
 </dd><dt id="uv-python-list--show-urls"><a href="#uv-python-list--show-urls"><code>--show-urls</code></a></dt><dd><p>Show the URLs of available Python downloads.</p>
@@ -3519,8 +3518,7 @@ uv python install [OPTIONS] [TARGETS]...
 <p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-install--pypy-mirror"><a href="#uv-python-install--pypy-mirror"><code>--pypy-mirror</code></a> <i>pypy-mirror</i></dt><dd><p>Set the URL to use as the source for downloading PyPy installations.</p>
 <p>The provided URL will replace <code>https://downloads.python.org/pypy</code> in, e.g., <code>https://downloads.python.org/pypy/pypy3.8-v7.3.7-osx64.tar.bz2</code>.</p>
 <p>Distributions can be read from a local directory by using the <code>file://</code> URL scheme.</p>
-</dd><dt id="uv-python-install--python-downloads-json-url"><a href="#uv-python-install--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations.</p>
-<p>Note that currently, only local paths are supported.</p>
+</dd><dt id="uv-python-install--python-downloads-json-url"><a href="#uv-python-install--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations</p>
 </dd><dt id="uv-python-install--quiet"><a href="#uv-python-install--quiet"><code>--quiet</code></a>, <code>-q</code></dt><dd><p>Use quiet output.</p>
 <p>Repeating this option, e.g., <code>-qq</code>, will enable a silent mode in which uv will write no output to stdout.</p>
 </dd><dt id="uv-python-install--reinstall"><a href="#uv-python-install--reinstall"><code>--reinstall</code></a>, <code>-r</code></dt><dd><p>Reinstall the requested Python version, if it's already installed.</p>
@@ -3612,8 +3610,7 @@ uv python upgrade [OPTIONS] [TARGETS]...
 <p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-upgrade--pypy-mirror"><a href="#uv-python-upgrade--pypy-mirror"><code>--pypy-mirror</code></a> <i>pypy-mirror</i></dt><dd><p>Set the URL to use as the source for downloading PyPy installations.</p>
 <p>The provided URL will replace <code>https://downloads.python.org/pypy</code> in, e.g., <code>https://downloads.python.org/pypy/pypy3.8-v7.3.7-osx64.tar.bz2</code>.</p>
 <p>Distributions can be read from a local directory by using the <code>file://</code> URL scheme.</p>
-</dd><dt id="uv-python-upgrade--python-downloads-json-url"><a href="#uv-python-upgrade--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations.</p>
-<p>Note that currently, only local paths are supported.</p>
+</dd><dt id="uv-python-upgrade--python-downloads-json-url"><a href="#uv-python-upgrade--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations</p>
 </dd><dt id="uv-python-upgrade--quiet"><a href="#uv-python-upgrade--quiet"><code>--quiet</code></a>, <code>-q</code></dt><dd><p>Use quiet output.</p>
 <p>Repeating this option, e.g., <code>-qq</code>, will enable a silent mode in which uv will write no output to stdout.</p>
 </dd><dt id="uv-python-upgrade--reinstall"><a href="#uv-python-upgrade--reinstall"><code>--reinstall</code></a>, <code>-r</code></dt><dd><p>Reinstall the latest Python patch, if it's already installed.</p>
@@ -3686,8 +3683,7 @@ uv python find [OPTIONS] [REQUEST]
 <p>Other command-line arguments (such as relative paths) will be resolved relative to the current working directory.</p>
 <p>See <code>--directory</code> to change the working directory entirely.</p>
 <p>This setting has no effect when used in the <code>uv pip</code> interface.</p>
-<p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-find--python-downloads-json-url"><a href="#uv-python-find--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations.</p>
-<p>Note that currently, only local paths are supported.</p>
+<p>May also be set with the <code>UV_PROJECT</code> environment variable.</p></dd><dt id="uv-python-find--python-downloads-json-url"><a href="#uv-python-find--python-downloads-json-url"><code>--python-downloads-json-url</code></a> <i>python-downloads-json-url</i></dt><dd><p>URL pointing to JSON of custom Python installations</p>
 </dd><dt id="uv-python-find--quiet"><a href="#uv-python-find--quiet"><code>--quiet</code></a>, <code>-q</code></dt><dd><p>Use quiet output.</p>
 <p>Repeating this option, e.g., <code>-qq</code>, will enable a silent mode in which uv will write no output to stdout.</p>
 </dd><dt id="uv-python-find--script"><a href="#uv-python-find--script"><code>--script</code></a> <i>script</i></dt><dd><p>Find the environment for a Python script, rather than the current project</p>